1. Field of the Invention
The invention relates generally to a combined percutaneous imaging marker and localizing wire for imaging and surgically identifying an area of interest within a tissue mass. More particularly, the invention relates to a combined percutaneous imaging marker and localizing wire having a connection enabling separation of the localizing wire from the imaging marker after placement of the imaging marker in the tissue mass.
2. Description of the Related Art
Tissue biopsy using a biopsy cannula is a well- known procedure for diagnosing the presence of a malignancy in a tissue mass comprising a tissue anomaly, such as a lesion. If the results of the biopsy indicate the presence of a malignancy, a follow-up surgical procedure involving excision of the lesion is frequently performed. In certain tissue masses, such as breast tissue, it may be difficult to locate the lesion through palpation or visual observation. Contemporary imaging techniques can image a lesion slightly larger than the size of a subsequent biopsy specimen. Thus, after the biopsy specimen is taken, the remaining lesion can be too small to be imaged, making it difficult to find the lesion for surgical excision.
This is particularly true of suspected breast tissue malignancies, where the accepted medical approach is to evaluate and, if necessary, treat the suspected malignancy at the earliest possible time. To ensure that the lesion can be located after the biopsy, a marker is frequently inserted into the tissue mass through the biopsy cannula to locate the lesion for further evaluation using imaging techniques, such as radiography, ultrasound, or MRI. The sole purpose of the marker is to provide an imageable reference for locating the lesion.
If subsequent evaluation of the biopsy sample reveals the absence of a malignancy, the marker is typically used for follow-up evaluation at a subsequent time, which may be several months, to confirm either the continued absence of a malignancy or the development of a further change in the tissue mass indicating the need for further evaluation.
If subsequent evaluation of the biopsy sample reveals the presence of a malignancy, surgery is frequently performed. While the marker can locate the lesion through imaging techniques, it is inadequate as a guide for the surgeon to quickly locate the lesion with minimal trauma to the surrounding tissue. Consequently, a localizing wire is typically inserted with the marker being used to guide the insertion of the localizing wire. The localizing wire has a metal shaft that terminates in a folded portion forming an anchor for anchoring the localizing wire in the tissue mass. The shaft extends from the anchoring structure to the exterior of the body to be followed by the surgeon in locating the lesion. The localizing wire is typically removed during the surgery.
The decision to perform surgery is typically made after the biopsy has been taken and the marker has been placed. Thus, it is necessary to place the localizing wire in a separate procedure, again involving the insertion of a cannula into the tissue mass. This can be an extremely painful procedure for the patient. The procedure is also time-consuming and costly. Additionally, while the marker is used to relocate the lesion for placement of the localizing wire, it is still possible to mislocate the localizing wire, particularly if the marker has moved. In such a case, the lesion may not be sufficiently excised, or excess, healthy tissue may be unnecessarily excised.
It would be convenient for the patient if the separate insertion procedure for the localizing wire could be eliminated upon a determination that the biopsy specimen was malignant. It would be an improvement, both in cost and patient health, if the surgical excision of the lesion could be accomplished without the intervening insertion of the localizing wire.